CGI  (Common Gateway Interface)

 CGI is a standard way for a Web server to pass a Web user's request to an application program and to receive data back to forward to the user. The most popular languages for CGI applications are: C, C++, Java, and Perl. 
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 An alternative to a CGI application is Microsoft's Active Server Page (ASP), in which a script embedded in a Web page is executed at the server before the page is sent. 

CGI City
Reference and tutorials

CGI Directory
The most comprehensive archive of CGI scripts and related materials on the Web

CGI Security
CERN (European Organization for Nuclear Research)

hostedscripts.com
 Free  remotely hosted CGI scripts

MegaCGI
A fast growing archive of Perl cgi scripts aim to provide webmasters with a range of tools & utilities to build and promote their sites as well as add interactivity to enhance user experience and thereby increase loyalty and repeat visitors.

Mycgiscripts
 Free   CGI scripts, links & resources

The CGI Resource Index
Thousands of pre-made CGI's written in Perl, C, C++, and other languages!

The Freescripts.com
Ready built free CGI scripts written in PERL

 Perl 

Introduction to PerlScript
By Matt Sergeant

Perl Help, programmer's reference

Perl Mongers

Perl Reference

 PHP 

Home of PHP
Introductory Tutorial

Home of PHP

Introduction to PHP - Zend

PHP Server Script from The Gibin Software House
 Free  PHP-scripts that implement the basic services
@Accounts
@SmartNews
@SmartForum
@SmartVoting
@SmartSend
@SmartEducation

PHP/MySQL Tutorial

The PHP Resource Index